diff --git a/S2OJ/1664/1664.cpp b/S2OJ/1664/1664.cpp
new file mode 100644
index 00000000..7ef8687d
--- /dev/null
+++ b/S2OJ/1664/1664.cpp
@@ -0,0 +1,42 @@
+#include <iostream>
+#include <numeric>
+
+using std::cin;
+using std::cout;
+const char endl = '\n';
+
+const int N = 1e5 + 5;
+
+int n, m, c[N];
+
+int main() {
+    std::ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    cin >> n >> m;
+
+    while (n--) {
+        int l, r;
+
+        cin >> l >> r;
+
+        l--;
+
+        for (int i = 1, j = 0; i <= r; i = j + 1) {
+            if (l / i == 0) j = r;
+            else j = std::min(l / (l / i), r / (r / i));
+
+            if (r / i - l / i > 0) {
+                c[i]++, c[j + 1]--;
+            }
+        }
+    }
+
+    std::partial_sum(c + 1, c + 1 + m, c + 1);
+
+    for (int i = 1; i <= m; i++) {
+        cout << c[i] << endl;
+    }
+
+    return 0;
+}
diff --git a/S2OJ/1664/data/ex_souvenir1.in b/S2OJ/1664/data/ex_souvenir1.in
new file mode 100644
index 00000000..f669dc32
--- /dev/null
+++ b/S2OJ/1664/data/ex_souvenir1.in
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:f51ed31e9d7fac03d21024c578a6a0085902f3e843f624f31f6f6a0b8e7f859e
+size 16
diff --git a/S2OJ/1664/data/ex_souvenir1.out b/S2OJ/1664/data/ex_souvenir1.out
new file mode 100644
index 00000000..41edd091
--- /dev/null
+++ b/S2OJ/1664/data/ex_souvenir1.out
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:c98f5e8f9ccc98857c763243e8553e05af3c44ea109425b76dd8c0e1bc01429a
+size 6
diff --git a/S2OJ/1664/data/ex_souvenir2.in b/S2OJ/1664/data/ex_souvenir2.in
new file mode 100644
index 00000000..65f0a61b
--- /dev/null
+++ b/S2OJ/1664/data/ex_souvenir2.in
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:04225e04887fc95f3011be38c3dda5882b784cbe6ef543006438a37909b35a55
+size 32
diff --git a/S2OJ/1664/data/ex_souvenir2.out b/S2OJ/1664/data/ex_souvenir2.out
new file mode 100644
index 00000000..85ee7a6f
--- /dev/null
+++ b/S2OJ/1664/data/ex_souvenir2.out
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:5ce792c02415e5c242c3b7bf177ce4a71b2c74b4c3d2fd364b21c3d8b38dca38
+size 18
diff --git a/S2OJ/1664/data/problem.conf b/S2OJ/1664/data/problem.conf
new file mode 100644
index 00000000..230a6ca7
--- /dev/null
+++ b/S2OJ/1664/data/problem.conf
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:cf10bef8123b7dbe605f85af53b1cfe2907cdce2bdc7c9f62469268b95861653
+size 185
diff --git a/S2OJ/1664/data/souvenir1.in b/S2OJ/1664/data/souvenir1.in
new file mode 100644
index 00000000..1cb3efc1
--- /dev/null
+++ b/S2OJ/1664/data/souvenir1.in
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:7bd43d67c0e33965b6471d9052e67b14bf3f12dd6885dad1a1beca03dd6a1c81
+size 1748
diff --git a/S2OJ/1664/data/souvenir1.out b/S2OJ/1664/data/souvenir1.out
new file mode 100644
index 00000000..e9cf783f
--- /dev/null
+++ b/S2OJ/1664/data/souvenir1.out
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:08db93fd17e5ffc224d8deb1ff99d60d5ec6c37c2f745fbffe9c4cc7ceb06595
+size 786
diff --git a/S2OJ/1664/data/souvenir10.in b/S2OJ/1664/data/souvenir10.in
new file mode 100644
index 00000000..48b56d2e
--- /dev/null
+++ b/S2OJ/1664/data/souvenir10.in
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:bd5f933ad8f8e117a51e6b6e9093ba14f12d919d0810ae624e2b18c794faa4e5
+size 2524194
diff --git a/S2OJ/1664/data/souvenir10.out b/S2OJ/1664/data/souvenir10.out
new file mode 100644
index 00000000..1476da20
--- /dev/null
+++ b/S2OJ/1664/data/souvenir10.out
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:1c6afaeb4643a4033bab481d8b0c7f6d6bd4f688c494764df9f4d8f5746df406
+size 699956
diff --git a/S2OJ/1664/data/souvenir2.in b/S2OJ/1664/data/souvenir2.in
new file mode 100644
index 00000000..69b5fe5e
--- /dev/null
+++ b/S2OJ/1664/data/souvenir2.in
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:98e4e5c1bae940b8f2b581bf3dd27957a9eb467344d9a15e1243cc250c8e48d1
+size 2226
diff --git a/S2OJ/1664/data/souvenir2.out b/S2OJ/1664/data/souvenir2.out
new file mode 100644
index 00000000..d4afa917
--- /dev/null
+++ b/S2OJ/1664/data/souvenir2.out
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:1fe06046a87bb3269e104eaa9a881d26a6b67068cfb9d025e51fee82578a4161
+size 1758
diff --git a/S2OJ/1664/data/souvenir3.in b/S2OJ/1664/data/souvenir3.in
new file mode 100644
index 00000000..8114997c
--- /dev/null
+++ b/S2OJ/1664/data/souvenir3.in
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:225fa062a78ba2c1b0fbf039ffcb9ee719fdd717f71a84147bb72ecc7ed9934a
+size 2266721
diff --git a/S2OJ/1664/data/souvenir3.out b/S2OJ/1664/data/souvenir3.out
new file mode 100644
index 00000000..2412a57d
--- /dev/null
+++ b/S2OJ/1664/data/souvenir3.out
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:964924fac71066178259ef3712a1be41bd929f2bc2eec8d3e217bae546b06b00
+size 24685
diff --git a/S2OJ/1664/data/souvenir4.in b/S2OJ/1664/data/souvenir4.in
new file mode 100644
index 00000000..28958b4f
--- /dev/null
+++ b/S2OJ/1664/data/souvenir4.in
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:810d1293fa04dbd6a584b9c2c04eb18dcaac035cbf34b2c33d63677bb6dcb6d9
+size 2335814
diff --git a/S2OJ/1664/data/souvenir4.out b/S2OJ/1664/data/souvenir4.out
new file mode 100644
index 00000000..b6b447f6
--- /dev/null
+++ b/S2OJ/1664/data/souvenir4.out
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:c2b76004517986e643cf021b6b01ee4fa8d0796cc51f213f09ea98b49c374724
+size 6774
diff --git a/S2OJ/1664/data/souvenir5.in b/S2OJ/1664/data/souvenir5.in
new file mode 100644
index 00000000..2ce8970e
--- /dev/null
+++ b/S2OJ/1664/data/souvenir5.in
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:a5bcc17aea8b88f6521f2e4598141e5890e72e044b915ba293aa5e93fdd274c7
+size 47751
diff --git a/S2OJ/1664/data/souvenir5.out b/S2OJ/1664/data/souvenir5.out
new file mode 100644
index 00000000..65c07810
--- /dev/null
+++ b/S2OJ/1664/data/souvenir5.out
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:4120fee209c6e654687eceb962cb606c8ea635cea849d0e1589046b8792fa567
+size 24401
diff --git a/S2OJ/1664/data/souvenir6.in b/S2OJ/1664/data/souvenir6.in
new file mode 100644
index 00000000..dab2cd0b
--- /dev/null
+++ b/S2OJ/1664/data/souvenir6.in
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:59aa9ce93f7d9b6efce6fdb980ca38e8544cdf1d8ae2b1e2cb1c32b57f0f84b4
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diff --git a/S2OJ/1664/data/souvenir6.out b/S2OJ/1664/data/souvenir6.out
new file mode 100644
index 00000000..b28f0ba4
--- /dev/null
+++ b/S2OJ/1664/data/souvenir6.out
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:1f71ea706b50db522970785e7c43b166064d65d5875ad74f44dc3ec55b5cd536
+size 24364
diff --git a/S2OJ/1664/data/souvenir7.in b/S2OJ/1664/data/souvenir7.in
new file mode 100644
index 00000000..834bc559
--- /dev/null
+++ b/S2OJ/1664/data/souvenir7.in
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:b88d904762c119129c470f7b69d551123c3b9c4ecbcd4fcb6f99f6ce71bad545
+size 2570792
diff --git a/S2OJ/1664/data/souvenir7.out b/S2OJ/1664/data/souvenir7.out
new file mode 100644
index 00000000..f0653681
--- /dev/null
+++ b/S2OJ/1664/data/souvenir7.out
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:5f7333a266d864e18edb1a73f288ca288a768d26eff284b6a72f1eac9b4ea96a
+size 422628
diff --git a/S2OJ/1664/data/souvenir8.in b/S2OJ/1664/data/souvenir8.in
new file mode 100644
index 00000000..4ac2f452
--- /dev/null
+++ b/S2OJ/1664/data/souvenir8.in
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
+oid sha256:82a1953edbc2099b0ce09c70c0c7b5e2a652818703340856bab84fceef4d6e52
+size 2750562
diff --git a/S2OJ/1664/data/souvenir8.out b/S2OJ/1664/data/souvenir8.out
new file mode 100644
index 00000000..fdc25f60
--- /dev/null
+++ b/S2OJ/1664/data/souvenir8.out
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
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diff --git a/S2OJ/1664/data/souvenir9.in b/S2OJ/1664/data/souvenir9.in
new file mode 100644
index 00000000..10667a24
--- /dev/null
+++ b/S2OJ/1664/data/souvenir9.in
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
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diff --git a/S2OJ/1664/data/souvenir9.out b/S2OJ/1664/data/souvenir9.out
new file mode 100644
index 00000000..2cd010b3
--- /dev/null
+++ b/S2OJ/1664/data/souvenir9.out
@@ -0,0 +1,3 @@
+version https://git-lfs.github.com/spec/v1
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